mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-06 02:50:49 +09:00
29811d6e19
DPNIs and DPSW objects can connect and disconnect at runtime from DPMAC objects on the same fsl-mc bus. The DPMAC object also holds "ethtool -S" unstructured counters. Those counters are only shown for the entity owning the netdev (DPNI, DPSW) if it's connected to a DPMAC. The ethtool stringset code path is split into multiple callbacks, but currently, connecting and disconnecting the DPMAC takes the rtnl_lock(). This blocks the entire ethtool code path from running, see ethnl_default_doit() -> rtnl_lock() -> ops->prepare_data() -> strset_prepare_data(). This is going to be a problem if we are going to no longer require rtnl_lock() when connecting/disconnecting the DPMAC, because the DPMAC could appear between ops->get_sset_count() and ops->get_strings(). If it appears out of the blue, we will provide a stringset into an array that was dimensioned thinking the DPMAC wouldn't be there => array accessed out of bounds. There isn't really a good way to work around that, and I don't want to put too much pressure on the ethtool framework by playing locking games. Just make the DPMAC counters be always available. They'll be zeroes if the DPNI or DPSW isn't connected to a DPMAC. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com> Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.